/**
* Copyright (c) 2013, Institute of Information Systems (Sven Groppe and contributors of LUPOSDATE), University of Luebeck
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
* following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice, this list of conditions and the following
* disclaimer.
* - Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the
* following disclaimer in the documentation and/or other materials provided with the distribution.
* - Neither the name of the University of Luebeck nor the names of its contributors may be used to endorse or promote
* products derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
* GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package lupos.endpoint.server.format;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Collection;
import java.util.HashSet;
import java.util.Iterator;
import lupos.datastructures.bindings.Bindings;
import lupos.datastructures.items.Triple;
import lupos.datastructures.items.Variable;
import lupos.datastructures.queryresult.QueryResult;
/**
* This class is for returning the query-triples of a query
*/
public class QueryTriplesFormatter extends Formatter {
public QueryTriplesFormatter() {
super("Query-Triples", "text/n3");
}
@Override
public String getMIMEType(final QueryResult queryResult){
return "text/n3";
}
@Override
public void writeResult(final OutputStream os, final Collection<Variable> variables, final QueryResult queryResult) throws IOException {
final byte[] carriageReturn = "\n".getBytes();
// use HashSet for eliminating duplicates!
final HashSet<Triple> triples = new HashSet<Triple>();
// collect all query-triples!
final Iterator<Bindings> it = queryResult.oneTimeIterator();
while(it.hasNext()){
final Bindings bindings = it.next();
for(final Triple triple: bindings.getTriples()){
triples.add(triple);
}
}
// now write out all triples without any duplicates
for(final Triple triple: triples){
os.write(triple.toN3String().getBytes());
os.write(carriageReturn);
}
}
@Override
public boolean isWriteQueryTriples() {
return true;
}
}